At the Geological Society of America (GSA) meeting in Denver, a study was presented that challenges the established view of the "Big Five" mass extinctions. According to the results of work conducted using a new AI model, OneStrata, three of the five known mass extinctions were not sudden catastrophes but spanned millions of years. This is reported by RBC-Ukraine with reference to publications by the Geological Society of America.
How the AI model rewrote paleontology
The research was led by Professor Shuzhong Shen from Nanjing University (China) along with a group of colleagues. The work is based on the OneStrata model, built on a transformer architecture and operating on the principle of large language models (LLM): the algorithm predicts the "next value" in a sequence. However, instead of text tokens, OneStrata was trained on the OneStratigraphy paleontological dataset, containing information on millions of fossils collected from tens of thousands of locations across the planet. Previously, scientists grouped fossils into periods covering several million years, meaning changes occurring over shorter intervals remained invisible to traditional methods. The new model allowed for a temporal scale detail of up to 1000 years—orders of magnitude higher than previous capabilities.
The "Big Five" proved less sudden
Traditionally, five mass extinctions are identified in Earth's history—from the Ordovician-Silurian (about 440 million years ago) to the Cretaceous, when land dinosaurs disappeared. They are usually perceived as sharp turning points, "switches" in the history of life. However, the OneStrata analysis showed that three of the five events—the Late Devonian, Triassic, and Cretaceous—actually stretched over millions of years. The Late Devonian extinction, which took place about 360 million years ago, occurred gradually: biodiversity declined over approximately 50 million years. This means that what is described in textbooks as a single "event" was actually a long process of ecosystem degradation.
The Permian extinction—the only exception
The only truly rapid event among the "Big Five" turned out to be the Permian extinction (about 252 million years ago). According to the model, most living organisms disappeared in just 63,000 years—a geologically negligible period. This confirms that not all catastrophes are equal: the Permian event was indeed a "sharp blow," whereas the other three out of five were more of a protracted crisis that accumulated over millions of years.
Researchers' caveats and scientific debate
Shuzhong Shen emphasizes an important caveat: the model builds a curve of overall biodiversity. According to him, it is quite possible that some species were actively going extinct while new ones immediately took their place, so the general picture "looks smooth." This does not exclude local sharp collapses of individual groups of organisms. Furthermore, discussions continue in the scientific community regarding the very definition of a mass extinction: according to various estimates by researchers, there could have been anywhere from 3 to 20 such events in Earth's history. A unified criterion—what percentage of species extinction and over what period qualifies an event as "mass"—has not yet been developed.
The Sixth Extinction: what awaits us in the geological record
Many experts believe that our planet is currently experiencing a sixth mass extinction, caused by anthropogenic climate change, habitat loss, and other factors. The authors of the publication point to a paradox: millions of years later, the current crisis in the geological layers may also look only like a "blurred episode" in Earth's history—just as we see smooth declines on the graph today, behind which hide catastrophes for specific species. This raises an additional question about how capable modern paleontology is of catching sharp changes if they occur on a scale comparable to human history.
